WO1999039041A1

WO1999039041A1 - Smooth polyester fiber

Info

Publication number: WO1999039041A1
Application number: PCT/JP1999/000366
Authority: WO
Inventors: Jinichiro Kato; Katsuhiro Fujimoto
Original assignee: Asahi Kasei Kogyo Kabushiki Kaisha
Priority date: 1998-01-29
Filing date: 1999-01-28
Publication date: 1999-08-05
Also published as: KR20010034446A; ATE332404T1; DE69932231D1; KR100378857B1; JP3188687B2; TW554098B; EP1052325A4; EP1052325B1; ES2270576T3; EP1052325A1; DE69932231T2; US6468655B1

Abstract

A polyester fiber obtained by depositing a specific amount of a finishing agent comprising a combination in a specific proportion of (1) and aliphatic ester having a molecular weight of 300 to 800 and/or a mineral oil having a Redwood viscosity at 30 °C of 40 to 500 seconds, (2) a polyether having a structure comprising ethylene oxide units and propylene oxide units, (3) a nonionic surfactant, and (4) an ionic surfactant on a polyester fiber which comprises at least 90 wt.% polytrimethylene terephthalate and has a difference in refractive indices of 0.025 or higher. The polytrimethylene terephthalate fiber having the specific finishing agent adherent thereto and having a low coefficient of friction is capable of highly smoothly passing through processing steps after spinning, e.g., winding after spinning, stretching, unwinding from a bobbin or cheese, false twisting, weaving, etc. As a result, a polytrimethylene terephthalate fiber excellent in smoothness, wearing resistance, bindability, and antistatic properties is obtained.

Description

Description Smooth polyester fiber

Technical field

The present invention has excellent smoothness, abrasion resistance, convergence, and antistatic properties, and has a spinning process such as a winding process, a stretching process, unwinding from bobbins or cheese, false twisting, and weaving. It has excellent passability from the process to the post-processing, and the bobbin and cheese winding form is extremely good.As a result, the woven and knitted fabric has good quality such as elastic recovery, soft texture, and homogeneity. The present invention relates to a polytrimethylene terephthalate fiber suitable for use in clothing. Background art

Poly (methylene terephthalate) (hereinafter referred to as “polyethylene methylene terephthalate”) obtained by polycondensation of lower alcohol ester of terephthalic acid represented by terephthalic acid or dimethyl terephthalate with trimethylene glycol (1,3-propanediol). (Abbreviated as PTT) is a property similar to polyamide such as excellent elastic recovery, low elastic modulus (soft feel), and easy dyeing, and light resistance, heat setting, dimensional stability, and low It is an epoch-making polymer that has properties similar to polyethylene terephthalate (hereinafter abbreviated as PET) such as water absorption. PTT has been applied to products such as clothing, BCF carpets, brushes, tennis guts, etc., taking advantage of the above-mentioned features (Japanese Patent Application Laid-Open Nos. Hei 9-37224 and Hei 8-1-173). 244, JP-A-5-262628-2).

One of the fiber forms that can make the most of the above properties of PTT fiber is a false twist processing system. The false twist processing system for PTT fiber is more elastic than conventional synthetic fiber, for example, polyester fiber such as PET fiber. This is because it is rich in resilience and softness, making it extremely excellent as a raw material for stretch material (Japanese Patent Application Laid-Open No. 9-77837).

When spinning and false-twisting a polyester fiber represented by PET fiber, it is essential to apply a finish to the fiber surface. If spinning and false twisting are performed without applying a finishing agent to the fiber surface, friction, static electricity will increase, and fluff and yarn breakage will occur frequently, making industrial production impossible. When false twisting PET fibers, the finishing agent contains 70% by weight or more of a polyether copolymerized with polyoxyethylene and polyoxypropylene (hereinafter simply abbreviated as polyester). An agent is usually attached to the fiber surface (for example, Japanese Patent Application Laid-Open No. 63-57554). The reason for this is that the heat setting process in the false twist processing of PET fiber requires heating at 200 ° C or more, and the coefficient of friction increases to suppress heater contamination due to thermal deterioration. However, it is necessary to use a finishing agent mainly composed of polyether having excellent heat resistance.

In contrast, no optimal composition has been proposed for a finish for false twisting of PTT fibers. The reason for this is that until recently, there was no inexpensive way to obtain trimethylene glycol, which is a raw material for PTT, and research on industrial production of PTT fibers has not been sufficiently advanced.

When considering a false-twisting finish for PTT fibers, you may imagine that a PTT fiber has a similar chemical structure to PET fibers, so that a PET-firing finish can be used directly in PTT fibers. Absent. However, according to the study of the present inventors, PTT fibers and polyester fibers other than PTT fibers typified by PET fibers are as follows: (1) Physical properties of the fibers, in particular, PTT fibers have a large coefficient of friction and abrasion.

, ② The optimal temperature condition of the heat setting process in the false twisting process is greatly different. For PTT fiber, the heat setting temperature must be set low, and it was found that it was necessary to design a finishing agent suitable for 剤 Τ Τ fiber for two reasons.

First, we explain that Ρ Τ Τ fibers have a high coefficient of friction and abrasion.

Τ Τ Τ Fibers have the property that when they are stretched like elastic yarn, they easily shrink back to their original length because the molecules are largely bent into a Ζ shape. Due to these elastic properties, when rolls, guides, hot plates, pins, or single yarns come into contact with each other under tension during the spinning and processing stages, the contact area increases greatly, and as a result, the friction coefficient increases. Greatly increase. If spinning and drawing are continued in such a state, fluff is likely to occur. Furthermore, it was also found that if the fibers of the Ρ Τ Τ fibers were rubbed with each other or with a material other than Ρ Τ Τ fibers, the yarns were likely to fluff. Probably, this kind of abrasion is also due to the Ζ-shaped bent molecular structure.If such a Ζ-shaped structure is adopted, the intermolecular force between adjacent molecules is reduced, so that the cohesive force acting in the intermolecular direction It is estimated that the wear characteristics will decrease as a result. On the other hand, other polyester fibers, for example, Ρ Ρ fiber ゃ polybutylene terephthalate fiber, have almost no elastic properties because the molecular chains are almost completely extended. In addition, the intermolecular cohesion tends to increase. As a result, there are few friction and abrasion problems encountered with Ρ Τ Τ fibers. If 仮 Ε Τ fiber false twist finish is applied to Ρ Τ Τ fiber, polyether, which is the main component of the finish, has little effect in lowering the coefficient of friction, so fluff and yarn breakage occur frequently, resulting in industrial It cannot be used for

Next, it is explained that the optimum temperature of the heat setting process in the false twisting process must be set lower than that of the 撚 Τ Τ fiber. You.

As described above, the heat set temperature in false twisting of PET fiber exceeds 200 ° C, but according to the study of the present inventors, PTT fiber is practically at a temperature of 190 ° C or more. Can not be heat set. This is because, when a temperature exceeding 190 ° C. is applied to the PTT fiber, the strength and elongation are greatly reduced, and the fiber is liable to be cut. Accordingly, the heat set temperature in false twisting of PTT fibers is usually 140 to 190 ° C. Even at such a low heat set temperature, the glass transition point of the PTT fiber is lower than that of the PET fiber, so that it is possible to receive a sufficient heat set. Therefore, as a finishing agent for false twisting of PTT fibers, it is not necessary to ensure heat resistance exceeding 200 ° C, and therefore, a polyether component having a low effect of lowering the friction coefficient of the fiber surface is mainly used. It turns out that it is not necessary to use the finishing agent as a component.

As described above, there has been almost no study on a temporary agent suitable for PTT fiber or a finishing agent for weaving and knitting. At present, there is no suggestion about the necessity of designing the finishing agent in consideration of the twisting temperature condition or any solution.

Therefore, for the industrial production of PTT fiber, it is essential to design a finish that has the ability to solve the above-mentioned problems due to the unique fiber properties.

Japanese Patent Application Laid-Open Nos. 424,284 and 199,477 propose a finish for PET containing a liquid aromatic ester. However, even if this finish is applied to PTT fibers, the coefficient of kinetic friction does not decrease, and the generation of fluff cannot be suppressed. On the other hand, as for the finish of PTT fiber, it does not cover textiles for clothing, but fishing line using PTT has a silicon-based component or a Teflon-based component. A technique for applying a surface treatment finish is disclosed (JP-A-9-226046). However, if a finishing agent mainly composed of a silicone-based component or a Teflon-based component is used for PTT fibers for clothing, the finishing agent will not easily fall off during the fiber scouring process, and in addition, the antistatic property will be low. There are downsides when it comes down. Therefore, a fiber fabric using such a finishing agent can obtain only a product with a slimy feeling and a poor texture. As described above, the known technology includes spinning of PTT fiber, particularly PTT fiber for clothing. There is no suggestion for the design of finishing agents that are essential for solving the processing-specific friction and wear problems.

The purpose of the present invention is to achieve a high coefficient of friction unique to PTT fiber, excellent smoothness and abrasion resistance with a finishing agent attached, which eliminates problems of spinning due to the abrasion of the side of the fiber and the processability of processing. An object of the present invention is to provide a PTT fiber having convergence and antistatic properties.

A more specific object of the present invention is to improve the process passability from spinning to post-processing, such as a winding step, a stretching step, unwinding properties from bobbins and cheese, false twisting properties, knitting and weaving properties, It is an object of the present invention to provide a PTT fiber to which an improved finishing agent is attached, which can obtain a woven or knitted fabric of good quality such as elastic recovery, soft texture, and homogeneity. Disclosure of the invention

An object of the present invention is to provide a polyester fiber having a birefringence of 0.025 or more composed of 90% by weight or more of poly (trimethylene terephthalate) and (1) a molecular weight of 300 to 800. And / or 30 of the aliphatic ester. A mineral oil having a redwood viscosity of 40 to 500 seconds in C, (2) a polyether having a specific structure, (3) a nonionic surfactant, and (4) an ionic surfactant. As a composition component, at a specific ratio This is achieved by a polyester fiber having a specific amount of finish to be combined.

That is, the present invention is a polyester fiber comprising 90% by weight or more of polytrimethylene terephthalate and having a birefringence of 0.025 or more, and a finishing agent is applied to the surface of the fiber. 2 to 3% by weight, containing compounds (1) to (4) as essential components of the finish, and compounds (1) to (4) in the total amount of the finish. Is a polyester fiber characterized in that the total content thereof is 80 to 100% by weight.

(1) An aliphatic ester having a molecular weight of 300 to 800 and a content of 30 to 80% by weight with respect to the total amount of the finishing agent, or a resin or a resin having a resin viscosity of 40 to 5 at 30 ° C. 0 0 second mineral oil

(2) A polystyrene having a content of 2 to 60% by weight based on the total amount of the finishing agent, represented by the following structural formula, in which an ethylene oxide unit and a propylene oxide unit are randomly or block copolymerized. ether

R, one 0-(CH ₂ CH ₂₀ ) ni-(CH (CH ₃ ) CH ₂₀ ) n ₂ one R ₂

(Here, R i and R 2 are a hydrogen atom, an organic group having 1 to 50 carbon atoms, and n ₂ is 1 to 100.)

(3) A compound obtained by adding ethylene oxide or propylene oxide to an alcohol having 1 to 30 carbon atoms, a carboxylic acid having 5 to 30 carbon atoms, ethylene oxide or / and propylene oxide to amine or amide. And at least one compound selected from the group consisting of a non-ionic compound and a non-ionic compound, wherein the total number of moles of the oxide is 1 to 100, and the content of the total amount of the finishing agent is 5 to 40% by weight. Surfactant

(4) An ionic surfactant having a content of 2 to 20% by weight based on the total amount of the finishing agent

The polyester fiber of the present invention has the specific finishing agent As a result, the fiber-to-fiber kinetic friction coefficient is 0.3 to 0.45 and the fiber-to-metal kinetic friction coefficient is 0.17 to 0.3, and the spinnability and processability are improved. Good polyester fiber. The fiber-to-fiber kinetic friction coefficient is also a parameter that indicates the likelihood of fluffing due to rubbing between fibers. On the other hand, the fiber-metal kinetic friction coefficient is a parameter indicating the likelihood of generation of fluff due to friction between the fiber and a metal part such as a roll or a hot plate.

If the fiber-to-fiber kinetic friction coefficient is less than 0.3, the fibers are too slippery, and the spinning and stretching properties are rather reduced. On the other hand, if it exceeds 0.45, the friction between the fibers becomes too high, and the fibers are liable to be fluffed. On the other hand, if the fiber-metal kinetic friction coefficient is smaller than 0.17, the fiber slips too much on a surface such as a wool and the spinning / drawing property is rather deteriorated. If this coefficient exceeds 0.3, the friction becomes too high and fluff is likely to occur.

On the other hand, the fiber-fiber static friction coefficient is a parameter that indicates the quality of a roll of cheese or cheese. In the region where the fiber-to-fiber static friction coefficient is in the range of 0.27 to 0.4, the fibers can form burns and cheeses having excellent shape and unwinding properties.

In the polyester fiber of the present invention, the specific finish is applied to a fiber having a birefringence of 0.025 or more. PTT fiber with a birefringence of 0.025 or more has a firm orientation of the fiber surface molecules, so that the finish does not excessively soak into the fiber and the finish firmly covers the fiber surface. Thus, the performance of the finish can be maximized.

In addition, the fibers whose birefringence is thus specified exhibit excellent elastic recovery because the PTT molecules in the fibers are appropriately oriented, and the resulting fabric also has excellent elastic recovery. Show. Polyester other than PTT Fibers, for example, PET fibers, do not exhibit such excellent elastic recovery even if the birefringence is 0.025 or more. When the birefringence is less than 0.025, the molecules are easily oriented due to insufficient orientation of the molecules, so that the molecules have a low elastic recovery and are subject to slight temperature change or load during storage or transportation. Long-term storage of the fibers impairs the properties of the finish, as the fibers are easily degraded and the attached finish excessively soaks into the fibers.

Fibers having a birefringence of 0.05 or more, preferably 0.05 to 0.1, have a sufficient orientation of the fibers, so that false twist without a weaving or knitting process or stretching is performed. The friction characteristics do not decrease in the process and dyeing process.

The polyester fiber of the present invention has a birefringence of 0.025 to 0.05, which is particularly suitable for a fiber for drawing false twisting, and in which the molecules are appropriately oriented. As a result, there is no change in fiber performance during normal handling such as storage and transportation.

The polyester fiber of the present invention may be a multifilament or a monofilament, and may be either a long fiber or a short fiber. The fineness of the polyester fiber of the present invention is not particularly limited, but is usually 5 to 200 d in total fineness and 0.0001 to 10 d in single yarn fineness. The cross-sectional shape is not limited, such as a round shape, a triangular shape, a flat shape, and a star shape, and may be a solid fiber or a hollow fiber. BEST MODE FOR CARRYING OUT THE INVENTION

90% by weight or more of the polymer constituting the polyester fiber of the present invention is PTT obtained by polycondensation of terephthalic acid and 1,3-trimethylene glycol. One or more other copolymers or polymers within a range that does not impair the object of the present invention, that is, within a range of 10% by weight or less. More than that may be copolymerized or blended. Examples of such comonomers and polymers include oxalic acid, succinic acid, adipic acid, isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, cyclohexanedicarboxylic acid, ethylene glycol, butanediol, Cyclohexandimethanol, 5—sodium sulfeusophthalic acid, 5—tetrabutylphosphonium phosphonium salt, polyethylene glycol, polybutylene glycol , Polyethylene terephthalate, polybutylene terephthalate, and the like.

Also, if necessary, various additives such as anti-glazing agents, heat stabilizers, anti-foaming agents, flame retardants, antioxidants, ultraviolet absorbers, infrared absorbers, crystal nucleating agents, fluorescent brighteners, etc. May be copolymerized or mixed.

The polyester fiber of the present invention has a birefringence of 0.025 or more. In this range of birefringence, the fibers exhibit excellent elastic recovery because the PTT molecules in the fibers are appropriately oriented. The resulting fabric also exhibits excellent elastic recovery. Polyester fibers other than PTT, such as PET fibers, cannot exhibit such excellent elastic recovery even if the birefringence is 0.025 or more.

Also, when the finish of the present invention is applied to PTT fiber having a birefringence of 0.025 or more, the finishing agent does not excessively soak into the fiber because the fiber surface molecules are oriented firmly. Since the fiber surface is covered firmly, the performance of the finishing agent can be maximized. When the birefringence is less than 0.025, molecules are easily moved due to insufficient molecular orientation. Therefore, the yarn cannot be used for the purpose of the present invention because the yarn has a low elastic recovery property and the yarn is easily deteriorated by a slight temperature change or load during storage or transportation. Also, the attached finishing agent will excessively soak into the fiber, and if stored for a long period of time, will impair the properties of the finishing agent. Birefringence of 0.025 to 0.05 The fibers are particularly suitable for fibers for false twisting while being drawn. Fibers having such a birefringence have the same fiber performance during normal handling such as storage and transportation because the P τ T molecules are appropriately oriented. It shows excellent stretchability, false twisting properties, and crimping properties. In addition, since the fibers having a birefringence of 0.05 or more, preferably 0.05 to 0.1, have sufficient orientation of the PTT fibers, the fibers do not require a weaving process or stretching. The fabric can be processed through a twisting step, a dyeing step, and the like.

The polyester fiber of the present invention comprises 90% by weight or more of PTT, has a birefringence of 0.025 or more, and has the following finishing agent attached to the fiber. Utilizing the excellent elastic recovery properties and soft texture of the product to the maximum, the processability from spinning to false twisting is extremely good, resulting in elastic recovery and softness as a woven fabric. Good quality such as homogeneity can be obtained.

In the present invention, the finish refers to an organic mixture adhering to the fiber surface.

The finish used in the present invention contains the compounds (1) to (4) as essential components as its constituent components, and the total amount of the compounds (1) to (4) in the total amount of the finish Is 80 to 100% by weight.

(1) An aliphatic ester having a molecular weight of 300 to 800 and a content of 30 to 80% by weight based on the total amount of the finishing agent, or a redwood viscosity at 30 ° C of 40 to 5 0 0 second mineral oil

(2) The content of the finishing agent is 2 to 60% by weight, represented by the following structural formula, wherein ethylene oxide units and propylene oxide units are randomly or block copolymerized. Polyether

R,-0-(CH ₂ CH ₂ 0) η,-(CH (CH ₃ ) CH ₂ 0) n ₂ -R ₂

1 o (Here,, R 2 are a hydrogen atom and an organic group having 1 to 50 carbon atoms, and n, and n ₂ are 1 to 100.)

(3) a compound in which ethylenoxide or propylenoxide is added to an alcohol having 1 to 30 carbon atoms, a carboxylic acid having 1 to 30 carbon atoms, an amine or an amide or ethylenoxide or / and At least one compound selected from compounds to which propylene oxide is added, the added mole number of the total amount of the oxide is 1 to 100, and the content relative to the total amount of the finishing agent is 5 to 40% by weight. Certain nonionic surfactants

(4) A surfactant having a content of 2 to 20% by weight based on the total amount of the finishing agent.

[1] Compound (1)

The compound (1), which is the first essential component of the finishing agent, is an aliphatic ester having a molecular weight of 300 to 800 and / or 30. It is a mineral oil with a redwood viscosity of 40 to 500 seconds at C.

These aliphatic esters and / or mineral oils are components necessary for improving the smoothness of the PTT fiber and reducing its friction coefficient. Examples of the aliphatic ester include various synthetic products and natural fats and oils. In particular, it is preferable to use a synthetic aliphatic ester having a linear structure to improve smoothness.

Examples of the aliphatic esters of synthetic products include monoesters, diesters, triesters, tetraesters, pentaesters, and hexesters. From the viewpoint of smoothness, use of monoester, diester, and triester is preferred. If the molecular weight of the aliphatic ester is less than 300, the strength of the oil film becomes too low and the oil is easily separated from the fiber surface with a guide roll to reduce the smoothness of the fiber or to reduce steam. There is a problem that the pressure is too low and it scatters during the process and deteriorates the working environment. If the molecular weight of the aliphatic ester exceeds 800, the viscosity of It is not preferable because the smoothness and the sizing property are reduced because the property becomes too high. Aliphatic polyesters having a molecular weight of from 300 to 550 are the most preferred aliphatic esters because they exhibit particularly good smoothness. Specific examples of preferred synthetics include isooctyl stearate, octyl stearate, octyl palmitate, isooctyl palmitate, 2-ethylhexyl stearate, lauric acid. Oleinole, isotridecyl stearate, oleyl oleate, dioleyl adipate, glyceryl trilaurate and the like. Of course, two or more aliphatic esters may be combined. Particularly preferred are octyl stearate, olein oleate, lauryl oleate and oleyl oleate. Among these aliphatic esters, from the viewpoint of excellent smoothness, aliphatic esters composed of a monovalent carboxylic acid and a monovalent alcohol are particularly preferable in terms of molecular structure. When it is desired to increase the heat resistance, it is preferable to use an aliphatic ester having a molecular weight of from 400 to 800. In this case, a part of the hydrogen atoms may be substituted with a group having a hetero atom such as an oxygen atom or a sulfur atom, for example, an ether group, an ester group, a thioester group, a sulfide group, or the like.

Examples of the mineral oil include paraffinic, naphthenic, and aromatic oils. From the viewpoint of improving smoothness, it is preferable to use paraffinic or naphthenic mineral oil. Of course, two or more mineral oils may be combined. As the mineral oil, one having a redwood viscosity at 30 ° C of 40 to 500 seconds is preferably used. Mineral oils of less than 40 seconds may be easily scattered and have a small effect, and if they are more than 500 seconds, the viscosity is too high and the effect of improving smoothness is reduced. The redwood viscosity of the mineral oil is preferably between 50 and 400 seconds.

Content of aliphatic ester and / or mineral oil in the finish of the present invention Is required to be 30 to 80% by weight in order to enhance smoothness. If the amount is less than 30% by weight, the smoothness is insufficient, and if the amount is 80% by weight, the smoothness becomes too high, and the burned fiber or wound cheese form becomes unsatisfactory. When used for false twisting, the content is preferably 30 to 60% by weight, and when used for woven or knitting, high smoothness is required, so that the content is preferably 50 to 70% by weight.

[2] Compound (2)

The second essential component of the finish is a polyether represented by the formula (2). Compound (2) has the function of enhancing the strength of the oil film formed on the fiber surface by the finish, and is a necessary component to dramatically improve the abrasion, which is a problem of PTT fibers, by adding it. . In particular, when the fibers are rubbed in the spinning, drawing process, false twisting process, and weaving process, the fibers exhibit a remarkable effect when they become less fluffy.

(2) R 1 — 0-(CH ₂ CH ₂ 0) η,-(CH (CH ₃ ) CH ₂ 0) n ₂ — R ₂ where R,, R z are a hydrogen atom, a carbon number of 1 to And up to 40 organic groups, and n ₂ is from 1 to 100. Here, even if the organic group is a hydrocarbon group, a part or all of the hydrocarbon group may be an ester group, a hydroxyl group, an amide group, a carboxyl group, a halogen atom, a sulfonate group, or the like. It may be substituted with a group or element having a hetero atom. Preferably, the hydrogen atom,, R ₂ is an aliphatic alcohol, an aliphatic carboxylic acid, an aliphatic amine, or an aliphatic amide residue, and has 5 carbon atoms. ~ 18 is preferred. In the compound (2), the propylene oxide unit and the ethylene oxide unit may be a random copolymer or a block copolymer. In particular, when the weight ratio of propylene oxide unit / ethylenoxide unit is from 20/80 to 70/30, the effect of suppressing abrasion is high. The weight ratio of oral pyrenoxide units / ethylenoxide units is 20 to 80/60/40. The molecular weight of the compound (2) is preferably from 400 to 2000, more preferably from 1500 to 2000. In this case, and and n ₂ adopt values corresponding to the molecular weight. This molecular weight is particularly important.If the molecular weight is less than 400, the effect of suppressing abrasion is small, and if the molecular weight exceeds 2000, the coefficient of static friction of the fiber becomes too low and the wound form becomes poor. Tend. Even more preferably, it is from 150 to 1500. The content of the compound (2) in the finish should be 2 to 60% by weight. If it is less than 2% by weight, the effect of improving abrasion resistance is small, and if it exceeds 60% by weight, the coefficient of static friction between fibers becomes too low, and the winding form becomes poor. When used for false twisting, the content is preferably 3 to 60% by weight, particularly preferably 5 to 40% by weight. When used for weaving, 5 to 30% by weight is preferred.

[3] Compound (3)

-The third essential component of the finishing agent is a compound of ethylene oxide or propylene oxide added to an alcohol of 1 to 30 carbon atoms, a carboxylic acid, amide or amide of 1 to 30 carbon atoms. It is at least one compound selected from compounds to which ethylene oxide and / or propylene oxide is added, the total number of moles of the oxide is 1 to 100, and the content with respect to the total amount of the finishing agent is 5 440% by weight of a nonionic surfactant.

The nonionic surfactant is a component necessary for imparting emulsifying properties for appropriately emulsifying the components of the finishing agent, bunching of the fibers, adhesion of the finishing agent, and abrasion resistance. This nonionic surfactant may be linear or branched in molecular structure, and may have a plurality of functional groups. Some or all of the hydrogen atoms are ester, hydroxyl, amide, carboxyl, halogen, or sulfonic acid groups. May be substituted with a group or element having a hetero atom.

The carbon number of the alcohol, carboxylic acid, amide, or amide is from 1 to 30, preferably from 5 to 30, and more preferably from the viewpoint of emulsifiability and convergence. Is 8 to 18. The number of moles of added ethylene oxide and propylene oxide is 1 to 100, and preferably 3 to 15 from the viewpoint of high smoothness. When an ethylene oxide unit and a propylene oxide unit coexist, either random copolymerization or block copolymerization may be used.

Specific examples of nonionic surfactants include polyoxyethylene stearyl ether, polyoxyethylene stearyl leuyl ether, polyoxyethylene oleyl ether, polyoxyethylene cetyl ether, and polyoxyethylene stearyl ether. Monobutyl ether copolymerized with polyoxyethylene lauryl ether and propylenoxydethylenoxide, polyquineethylene bisphenol A dilaurate, polyoxyethylene bisphenol A rauraylate Polyethylene bisphenol A distearate, Polyethylene bisphenol A stearate, Polyethylene bisphenol A georate, Polyethylene Oxyethylene bisphenol A rate, polyoxyethylene stearyla Min, polyoxyethylene laurilamin, polyoxyethylene oleamide, polyoxyethylene oleamide, polyoxyethylene laurate amide, poly Oxyethylene stearate amide, polyoxyethylene laurate ethanolate, polyoxyethylene oleate ethanolate, polyoxyethylene oleate diethanol amide, diethyle Triaminooleic acid amide, polyoxypropylene stearyl ether, polyoxypropylene bisphenol A stearate, polypropylene stearylamine, polypropylenoleate Etc. To

It is necessary that the content of these nonionic surfactants in the finishing agent is 5 to 40% by weight from the viewpoint of improving emulsifying properties, fiber bunching, finishing agent adhesion, and abrasion resistance. . If it is less than 5% by weight, the above performance is insufficient. On the other hand, if it exceeds 30% by weight, the friction becomes too high, and fluff is likely to occur. It is preferably from 5 to 30% by weight.

4] Compound (4)

The fourth essential component of the finish is an ionic surfactant. This ionic surfactant is a component necessary for imparting antistatic properties, abrasion resistance, emulsifying properties, and anti-wear properties to the fibers.

As the ionic surfactant, any of an anionic surfactant, a cationic surfactant, and an amphoteric surfactant may be used, and in particular, the use of an anionic surfactant is an antistatic property. It is preferable from the viewpoint of imparting abrasion resistance, emulsifying property and heat resistance, and in particular, a sulfonate compound, a phosphate salt, a higher fatty acid salt and the like are preferable. Of course, two or more kinds of anionic surfactants may be combined. Specific examples of preferred ionic surfactants include compounds (5) to (8), which are particularly excellent in antistatic property, abrasion resistance, emulsifying property, and water resistance.

(5) R ε-S 0 a-X

(6) (R 0-P (= 0) (0 X) ₂

₍₇₎ (R 7 one 0 - (R 8 one 0-) P (= 0) ( 0 X)

(8) R 9-C 00-X

Here, R to R ₉ are a hydrogen atom and an organic group having 4 to 40 carbon atoms. Here, even when the organic group is a hydrocarbon group, part or all of the hydrocarbon group is an ester group, a hydroxyl group, an amide group, a carboxy group, a halogen atom, a sulfonic acid group, or the like. It may be substituted with a group or element having another hetero atom. Preferably carbonized with 8 to 18 carbon atoms It is a hydrogen group. X is an alkali metal or an alkaline earth metal. It is necessary that the content of these nonionic surfactants in the finishing agent is 2 to 20% by weight from the viewpoint of improving antistatic properties. If the content is less than 2% by weight, the antistatic property, abrasion resistance, emulsifying property, and anti-yielding property are insufficient, and the fiber-to-fiber kinetic friction coefficient and the fiber-to-fiber static friction coefficient are too low, resulting in poor winding form. On the other hand, if the content exceeds 20% by weight, the friction becomes too high, and fluff is likely to be generated. When used for false twisting, the content is preferably 2 to 15% by weight, and when used for weaving, 5 to 15% by weight is preferred. In the finish containing the four essential components described above, the content of these essential components needs to be in the range of 80 to 100% by weight of the total amount of the finish. That is, the finishing agent used in the present invention may contain a finishing component other than the essential components of the present invention in a range that does not impair the object of the present invention, that is, less than 20% by weight. Although there is no particular limitation on such a finish component, in order to improve smoothness and spreadability of the finish on the fiber, a silicone compound such as dimethylsilicon, A compound obtained by adding about 3 to 100 moles of ethylene oxide or Z and propylene oxide to a part of the methyl group of tyl silicon via an alkyl group, and an organic compound having 5 to 18 carbon atoms. And the like. In addition to the compounds specified in the present invention, an imidazoline compound having a metal carbonate unit is contained in order to improve antistatic properties. It may contain an ester compound other than those defined in the present invention, for example, an ester having an ether group. Further, it may contain a known antiseptic, antiseptic, antioxidant and the like. The content is preferably 10% by weight or less, more preferably 7% by weight or less.

Finishes composed of the above constituents are not diluted as such, or 5 to 60% by weight, preferably 5 to 35% by weight in water. It can be dispersed and attached to fibers as an emulsion finish.

It is necessary that the amount of the finishing agent deposited on the fibers is 0.2 to 3% by weight. If the content is less than 0.2% by weight, the effect of the finishing agent is reduced. On the other hand, if it exceeds 3% by weight, the running resistance of the fiber becomes too large, and the finishing agent adheres to the rolls, hot plates, guides, etc., and contaminates them. When used for false twisted yarn, the content is preferably 0.3 to 1.0% by weight, particularly preferably 0.3 to 0.6% by weight, and when used for weaving and knitting, 0.4 to 1.0% by weight. It is 1.2% by weight, particularly preferably 0.5-1% by weight. Of course, some of the finishing agent may penetrate into the fiber.

In order to apply the finishing agent used in the present invention to the fiber, the polyester fiber of the present invention is applied at any time when the spun yarn is solidified during melt spinning. Normally, it is preferable to apply the fibers to the fiber before winding is performed. As a spinning method to which the application of the finishing agent is applied, a method in which an undrawn yarn is wound once and then drawn by a drawing machine, a method in which spinning and drawing are performed in one stage, and 200 to 400 m / m Any of a method of obtaining a semi-drawn yarn in min and a high-speed spinning in which spin drawing is performed at a spinning speed of 500 to 140 Om / min may be used. As above

Then, spinning is performed, and the obtained fiber is stretched to have an elongation of 25 to 180%, preferably 25 to 150%, and more preferably 35 to 130%. By performing the above, the birefringence of the polyester fiber of the present invention can be made 0.025 or more.

The fiber obtained as described above satisfies both the fiber-to-fiber kinetic friction coefficient of 0.3 to 0.45 and the fiber-to-metal kinetic friction coefficient of 0.17 to 0.3. It becomes a fiber with good processability. The fiber-to-fiber kinetic friction coefficient is a parameter that indicates the likelihood of fluffing due to rubbing between fibers. It is a tar. If it is less than 0.3, it will slip too much, and the spinning and stretching properties will be reduced. If it exceeds 0.45, the friction becomes too high, and fluff is likely to occur. Preferably, it is 0.3 to 0.42. The fiber-metal kinetic friction coefficient is a parameter indicating the likelihood of generation of fluff due to rubbing between the fiber and a metal part such as a roll / hot plate. If it is smaller than 0.17, it will slip too much, and the spinning and stretching properties will decrease. If it exceeds 0.3, the friction becomes too high, and fluff is likely to be generated. Preferably, it is 0.15 to 0.23.

Further, when the fiber-fiber static friction coefficient is 0.27 to 0.4, more preferable fibers are obtained. In addition, since the fiber-to-fiber static friction coefficient corresponds to the amount of polyether added, by adjusting the amount of polyether to make the fiber-to-fiber static friction coefficient 0.27 to 0.4, good wear resistance is obtained. And winding forms can be achieved. The fiber-to-fiber static friction coefficient is a parameter indicating the quality of the roll form of a burn or cheese. If it is less than 0.27, the coefficient of static friction is too small, and the wound form collapses. If it exceeds 0.4, the fiber becomes a fiber having a high friction coefficient, and the additivity decreases. Preferably, it is 0.28 to 0.35.

Further, the polyester fiber of the present invention usually shows the following fiber physical properties.

The strength of the polyester fiber of the present invention is preferably 3 g / d or more for a drawn yarn, and 1.0 g / d or more for a semi-drawn yarn. In the case of a drawn yarn, if it is less than 3 g / d, the tear strength and the burst strength of the obtained fabric may decrease depending on the use. Preferably, it is 4 gZd or more.

The elongation of the polyester fiber of the present invention is usually 25 to 180%. If the elongation is less than 25%, the abrasion resistance of the fiber is extremely low, and even if a finish described below is applied to such a fiber, the abrasion characteristics are poor. In some cases, it cannot be used practically. On the other hand, if the elongation exceeds 180%, the orientation of the fiber becomes insufficient, and the yarn may be easily deteriorated by a slight temperature change or load during storage or transportation. Preferably, to use as a drawn yarn, 35 to 55% is preferable to suppress generation of fluff, and to use as a semi-drawn yarn for performing false twisting, 4 to 55% is used. 0 to 130% is preferred.

In addition, the elastic recovery of the polyester fiber of the present invention at 20% elongation is

70% or more is preferred. By satisfying such an elastic recovery rate, the obtained fabric has extremely high stretchability. Preferably

80% or more.

The elastic modulus of the polyester fiber of the present invention is in the range of 10 to 30 g / d. By exhibiting such a low elastic modulus, the obtained fabric has an extremely soft texture. Preferably, the viscosity is 20 to 25 g Zd and the intrinsic viscosity of the polyester fiber of the present invention. 7] is preferably from 0.4 to 2.0, more preferably from 0.5 to 1.5, and even more preferably from 0.6 to 1.2. Within this range, fibers having excellent strength and spinnability can be obtained. When the intrinsic viscosity is less than 0.4, spinning becomes unstable because the melt viscosity of the polymer is too low, and the strength of the obtained fiber is low, which is not satisfactory. On the other hand, if the intrinsic viscosity exceeds 2.0, the melt viscosity is too high, and melt fracture or poor spinning occurs during spinning. Example

Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited by the description of Examples and the like. The main measured values in the examples were measured by the following methods. (1) Measurement of intrinsic viscosity

This intrinsic viscosity [] is measured using an Ostwald viscometer at 35 ° C and 0-chlorophenol. ? The ratio 77 sp ZC between the sp and the concentration C (g / 100 milliliters) was excluded from the concentration of zero, and the value was calculated according to the following equation.

[n] = 1 im (η s ρ / C)

C → 0

(2) Measurement of reddish viscosity

It measured according to JIS-K2283-19556.

(3) Measurement of birefringence

From the retardation observed on the fiber surface using an optical microscope and a compensator in accordance with Textile Handbook, Raw Materials, p. 969 (5th printing, 1978, Maruzen Co., Ltd.) I asked.

(4) Measurement of mechanical properties (strength, elongation, elastic modulus) of fiber

The measurement was performed according to JIS-L-1013.

(5) Measurement of elastic recovery

The fiber was attached to a tensile tester at a chuck distance of 20 cm, stretched to an elongation of 20% at a stretching speed of 20 cm / min, and left for 1 minute. After that, it is contracted again at the same speed, and a stress-strain curve is drawn. The elongation when the stress becomes zero during shrinkage is defined as the residual elongation (A). The elastic recovery was determined according to the following equation.

Elastic recovery rate = (2 0-A) / 2 0 X 1 0 0 (%) (6) Oiling rate

Based on JIS-L-113, the fiber was washed with ethyl ether, the ethyl ether was distilled off, and the amount of the pure oil adhering to the fiber surface was divided by the fiber weight to determine the oiling rate.

(7) Measurement of the number of yarn friction cuts The number of yarn friction cuts indicates the number of times the fibers are rubbed together before cutting occurs, and is a measure of the ease with which the fiber side surfaces are worn. In other words, the larger the number, the better the abrasion.

The number of yarn friction cuts is measured by a yarn friction binding tester manufactured by Toyo Seiki Seisaku-sho, Ltd.

(o. 890). The two ends of the yarn were tied together with two clasps lined up through pulleys. This clasp can reciprocate with a length of 2 Omm. The pulley was rotated and twisted twice, a load of 50 g was applied, and the clasp was reciprocated in 150 strokes Z minutes. The number of reciprocating motions can be measured with a counter, and the number of times until the yarn is cut was determined as the number of yarn friction cuts.

(8) Fiber-to-fiber static friction coefficient

Approximately 690 m of fiber was wrapped around the cylinder at 1.5 ° of twill angle with a tension of about 10 g, and 30.5 cm of the same fiber as above was wrapped around the cylinder. At this time, this fiber is on the cylinder and is parallel to the winding direction of the cylinder. A weight, in which the load expressed in grams is 0.04 times the total denier of the fiber hung on the cylinder, is tied to one end of the fiber hung on the cylinder and a strain gauge is attached to the other end. Connected. Next, rotate the cylinder at a peripheral speed of 0.01 emmZ seconds and measure the tension with a strain gauge. The fiber-to-fiber static friction coefficient f was determined from the tension thus measured according to the following equation.

f = 1 / ^ X 1 n (T 2 / Ύ 1)

Here, T, is the weight of the weight applied to the fiber, T ₂ is the average tension measured at least 25 times, In is the natural logarithm, and 7Γ is the pi.

(9) Dynamic friction coefficient between fibers

In the measurement method of (8), f when the peripheral velocity was 1 SmZmin was defined as the fiber-to-fiber dynamic friction coefficient. (10) Fiber-metal dynamic friction coefficient

It was measured under the following conditions using a U-meter manufactured by Eiko Ikki.

The fiber enters the friction body while applying 0.4 g Zd tension to the 25 mm diameter iron cylinder whose surface is finished in chrome satin (roughness 3 s). The kinetic friction coefficient of the fiber when the fiber was rubbed at a speed of 100 mZmin in an atmosphere of 25 ° C and 65% RH with the exit direction set to 90 ° was determined according to the following equation.

3 60 x 2 .3 0 ₂ 6/2 丁 β 10 g

2 π θ \ Τ,

Here, T! Entrance tension to friction body (tension equivalent to 0.4 g per denier)

T Tension on the exit side from the friction body

Θ 90 °

π Pi

(1 1) Scum generation

When weaving a plain weave using the fibers for the warp and weft, it was observed whether or not scum was generated around (1). The weaving was carried out using a loom 2A-103 of Tsudakoma Kogyo Co., Ltd. at a density of 38.1 cm and a weft density of 31.5 cm.

〇: Not generated

Δ: Occurred, but to a lesser extent.

X: Large amount of scum

(1 2) Generation of fluff

The fiber (yarn) is passed through the knitting needle, and the angle between the yarn path entering and exiting the knitting needle is 60. The cheese was wound at 2 mZmin for 5 hours under a tension of 0.6 g Zd for 5 hours, and the number of fluffs generated on the end face of the cheese was counted. ず Not generated

Δ 1 to 3 occurrences

X 3 or more occurrences

(13) Generation of static electricity

When weaving plain fabrics using fibers (yarns) as warps and wefts, it was examined whether static electricity was generated and the fibers sometimes approached each other when passing through a raft.

〇: Not seen

X: seen

(14) Shape evaluation of wound form

When a roll of 3 kg was prepared, it was observed whether or not the wound form collapsed.

〇: Not seen

X: seen

Reference Example 1 Synthesis of poly (methylene terephthalate) polymer

Dimethyl terephthalate (hereinafter abbreviated as DMT) and trimethylene glycol (1,3-pronondiol) were charged at a molar ratio of 1: 2, and 0.09% by weight of ZDMT (the unit is the amount of DMT) (A weight% with respect to the weight of the compound) and calcium acetate of 0.01% by weight of ZDMT were added thereto, and the temperature was gradually increased to complete the transesterification at 240 ° C. To the obtained transesterified product, trimethylphosphophosphate as a heat stabilizer 0.05% by weight ZDMT, an average particle size of 0.35 // m Then, the mixture was reacted at 270 ° C. for 2 hours. The intrinsic viscosity of the obtained polymer was 0.75. Next, this polymer was further subjected to solid-state polymerization under a nitrogen atmosphere at 215 ° C. for 5 hours to increase the intrinsic viscosity to 0.92. (Examples 1 to 8) The polymer obtained in Reference Example 1 was dried under a nitrogen atmosphere at 160 ° C. for 3 hours using a circulating drier to a moisture content of 30 ppm. The obtained dried polymer was put into an extruder, and extruded through a round spinning hole having a diameter of 0.23 mm x 36 pieces at a diameter of 2655 mm. The spun filament group was blown with cold air at 20 ° C. and 90% relative humidity at a speed of 0.4 m / s to be cooled and solidified. Using a refueling nozzle, the solidifying filaments were applied with the finishing agent shown in Table 1 as a 10% water-dispersed emulsion and wound on the yarn at 160 m / min. Next, the obtained undrawn yarn was drawn while passing through a hot roll at 55 ° C and a hot plate at 140 ° C so that the elongation became almost 40%, and 50 d / 3 6 The drawn yarn of f was obtained. The obtained fiber was a fiber consisting of PTT at 99% by weight or more.

All of the fibers to which the finish having the composition within the range specified in the present invention was adhered exhibited excellent spinning and drawability. In addition, the fibers obtained in any of the examples were high in elastic recovery, low in elastic modulus, and soft in touch.

[Comparative Examples 1 to 6]

Example 1 was repeated, changing the finish as described in Table 1. In Comparative Example 1, since an aromatic ester was used in place of the aliphatic ester, scum and fluff were generated due to a high fiber-to-fiber kinetic friction coefficient and a fiber-to-metal kinetic friction coefficient. Also, since it does not contain polyether, the number of yarn friction cuts is low.

In Comparative Example 2, a finishing agent containing no aliphatic ester, which is used for false twisted yarn of PET, was used. In this case, when the fiber-metal kinetic friction coefficient was high, fluff was generated when the fiber passed through the hot plate or the mouth. Also, fluff was generated in the fluff test. As a result, the number of yarn friction cuts decreased.

In Comparative Example 3, the aliphatic ester having a molecular weight lower than the range of the present invention was used. Was used. In this case, since the film strength of the finishing agent was reduced, the coefficient of kinetic friction between the fiber and the metal was increased, and fluff was generated when passing through a hot plate or a mouth. Also, fluff was generated in the fluff test.

In Comparative Example 4, an experiment was conducted using a finish containing an amount of polyether exceeding the range of the present invention. In this case, the fiber-to-fiber static friction coefficient was reduced, and the wound foam was greatly collapsed, and it was not possible to obtain a 3 kg winding burn.

In Comparative Example 5, the finishing agent out of the range of the present invention was adopted by using the finishing agent of Example 1 and lowering the oiling rate. In this case, the fiber-to-fiber kinetic friction coefficient and the fiber-to-metal kinetic friction coefficient were increased, and fluff and static electricity were generated.

Comparative Example 6 showed a finish in which the amount of ionic surfactant was outside the scope of the present invention. In this case, static electricity was generated. In addition, the fiber-to-metal kinetic friction coefficient was too low and slipping on the roll was observed.

[Comparative Example Ί]

The finish of Comparative Example 2 was used to adhere to PET fibers. In this case, although the fiber-to-fiber dynamic friction coefficient was out of the range of the PTT fiber of the present invention, the fiber could be spun and drawn without any problem. There was no problem with the fluff test. This indicates that the PET fiber has a lower coefficient of friction than the PTT fiber and at the same time is resistant to rubbing of the fiber-to-fiber. Further, the obtained fiber had a low elastic recovery property, a high elastic modulus and a hard feel.

(Comparative Example 8)

The birefringence of the undrawn yarn of Example 1 was 0.024, the strength was 1.6 d, and the elongation was 230%. If left at 20 ° C for 20 days, The physical properties changed over time and became very brittle. Such a phenomenon was not observed in the fibers of Examples 1 to 8.

(Example 9)

Using the finishing agent of Example 7, the spinning speed was set to 3500 m / min, and only spinning was performed. The birefringence of the obtained semi-drawn yarn is 0.062, the strength is 2.7 g / d, the elongation is 74%, the oiling rate is 0.41%, and the dynamic friction coefficient between fibers is The coefficient of kinetic friction between fiber and metal was 0.20, the coefficient of static friction between fiber and fiber was 0.29, and there was no problem in spinnability. Also, unlike the undrawn yarn of Comparative Example 8, this semi-drawn yarn had no change in fiber properties over time after standing at 20 ° C. for 20 days.

The semi-drawn yarn is heated at 160 ° C. while performing 1.25 times drawing at a processing speed of 450 mZ min using a SW46 SSD false twisting machine manufactured by Vamagu. Meanwhile, a crimped yarn of 360,000 TZm was prepared. There was no problem with the workability at this time. Moreover, the obtained processed yarn was rich in swelling and stretch, and had a soft texture.

(Comparative Example 9)

In Comparative Example 2, the spinning speed was set to 3500 m / min, and only spinning was performed. The birefringence of the obtained semi-drawn yarn is 0.066, the strength is 2.5 d, the elongation is 82%, the coefficient of kinetic friction between fiber and fiber is 0.39, and the coefficient of kinetic friction between fiber and metal is 0.32, the coefficient of static friction between fibers was 0.30. Due to the high coefficient of kinetic friction between fiber and metal, fluffing occurred during spinning.

False twisting was attempted on this semi-drawn yarn in the same manner as in Example 9, but a large amount of fluff was generated and could not be wound for a long time.

(Examples 10 to 12)

Performed using PTT with an intrinsic viscosity of 0.8 by changing the type of finish Example 1 was repeated. The fibers thus obtained consisted of more than 99% by weight of P-chome.

All of the fiber properties and the finish composition within the ranges specified in the present invention exhibited excellent spinning and drawing properties.

(Reference Example 2)

The drawn yarns obtained in Examples 5 and 8 were subjected to spindle rotation at 2750 rpm and false twists at 3650 T / m using an LS-2 false twisting machine manufactured by Mitsubishi Industrial Corporation. The false twisting was performed at an over feed rate of 4.1% and a false twist temperature of 16.5. In each case, it was excellent in stretchability and softness, and showed good false twistability without thread breakage.

On the other hand, in all of the fibers of Comparative Examples 1 to 6, thread breakage occurred frequently.o

(Reference Example 3)

Plain fabrics were prepared using the fibers of Examples 1, 5, 10 and Comparative Example 7 by the method described in "Method of measuring scum generation". When the fibers of Examples 1, 5, and 10 were used, the obtained plain woven fabric was soft and showed a stretchability of about 10% in the weft direction. It has a texture that cannot be obtained with conventional synthetic fabrics.

On the other hand, when the fiber of Comparative Example 7 was used, the hand was firm and did not show any stretchiness.

Table 2 Properties of PTT fiber with various finishing agents attached

In the table, W,, W ₂ , W ₃ and W, indicate the content (% by weight) of the compounds (1), (2), (3) and (4) in the total amount of the finish.

Polyethers are random copolymers.

Industrial applicability

The polyester fiber of the present invention solves the problems of high friction coefficient and easy wear of the side surface of the fiber, which are problems peculiar to pτT fiber, and has excellent smoothness, abrasion resistance, convergence, and antistatic properties. Excellent in processability from spinning to post-processing such as winding process, stretching process, unwinding from bobbin and cheese, false twisting process, weaving, etc., bobbin and cheese winding The form is extremely good. Thus, the PTT fiber to which the finish specified by the present invention has adhered can be processed into a knitted fabric having good quality such as elastic recovery, soft texture, and homogeneity.

The polyester fiber of the present invention is, of course, a textile material for clothing such as outerwear, innerwear, sportswear, swimwear, lining, pantyhose, tights, and raw yarn for sock artificial leather. It is also useful in applications such as carpet, flocky, artificial leather, gut, and artificial turf.

Claims

The scope of the claims

Polyester fibers having a birefringence of 0.025 or more are composed of at least 1.9% by weight of polytrimethyl terephthalate, and a finishing agent is applied to the surface of the fibers at an amount of 0.2% or more. 3% by weight, containing the compounds (1) to (4) as an essential component as a component of the finishing agent, and containing the compounds (1) to (4) in the total amount of the finishing agent. Polyester fiber characterized by having a total content of 80 to 100% by weight.

(1) Aliphatic ester having a molecular weight of 300 to 800 and a content of 30 to 80% by weight with respect to the total amount of the finishing agent, and a Z or a resin with a resin viscosity of 40 to 5 at 30 ° C. 0 0 second mineral oil

(2) Polyethylene oxide and propylene oxide units having a content of 2 to 60% by weight based on the total amount of the finishing agent and having a random or block copolymer of ethylene oxide units and propylene oxide units. ether

R,-0-(CH ₂ CH ₂ 0) η, one (CH (CH ₃ ) CH ₂₀ ) n ₂ one R ₂

(Where, and R 2 are a hydrogen atom and an organic group having 1 to 50 carbon atoms, and n and n ₂ are 1 to 100.)

(3) Compounds obtained by adding ethylene oxide or propylene oxide to an alcohol having 1 to 30 carbon atoms, carbon number] to 30 carboxylic acids, amines or amides, and ethylene oxide or propylene oxide. At least one compound selected from the compounds having an addition of 1 to 100, and the added mole number of the total amount of the oxide is 1 to 100, and the content relative to the total amount of the finishing agent is 5 to 40% by weight. Surfactant

2. The polyester fiber according to claim 1, wherein the molecular weight of the aliphatic ester is from 300 to 550.

3. The polyester fiber according to claim 1, wherein in the compound (2), the weight ratio of propylene oxide units to Z ethylenoxide units is 20 / 80-70 / 30.

4. In the compound (2), the weight ratio of propylene oxide units / ethylenoxide units is 20 / 80-70 / 30, and the molecular weight is from 150 to 200. The polyester fiber according to any one of claims 1 to 3, wherein

5. The polyester fiber according to claim 1, wherein the ionic surfactant is at least one compound selected from the following compounds (5) to (8).

(5) R ₅ -S 03 I X

(6) (R ₆ _ 0-) P (= 0) (0 X) ₂

(7) (R, - 0- ) (R 8 - 0 -) P (= 〇) (OX)

(8) R 9 C O O X

(Here, R _{5 to} R _S are a hydrogen atom, an organic group having 4 to 40 carbon atoms, and X is an alkali metal or an alkaline earth metal.)

6. 90% by weight or more of polyester fiber composed of polytrimethylene terephthalate and having a birefringence of 0.025 or more, and a finish of 0.3 to 1.0% by weight, containing the compounds (1) to (4) as essential components as constituents of the finishing agent, and the compounds (1) to ( 4) Polyester fiber characterized by having a total content of 80 to 100% by weight.

(1) Aliphatic ester having a molecular weight of from 300 to 800 and a content of 30 to 6 G% by weight based on the total amount of the finishing agent, and a resin or a resin having a viscosity of 40 to 5 at 30 ° C. 0 0 second mineral oil

(2) Ethylene oxide unit and propylene oxide represented by the following structural formula, wherein the content with respect to the total amount of the finishing agent is 5 to 40% by weight. Polyether with random or block copolymerized units

R, — 0— (CH ₂ CH ₂ 0) n! One (CH (CH ₃ ) CH ₂ 0) η, — R ₂

(Here, and R 2 are a hydrogen atom and an organic group having 1 to 50 carbon atoms, and η and n ₂ are 1 to 100.)

(3) a compound in which ethylene oxide or propylene oxide is added to at least one selected from alcohols, carboxylic acids, amides, and amides having 1 to 30 carbon atoms, and A nonionic surfactant having a total molar number of 1 to 100 and a content of 5 to 30% by weight based on the total amount of the finishing agent

(4) An ionic surfactant having a content of 2 to 15% by weight based on the total amount of the finishing agent

7.9% or more by weight of polyester methylene terephthalate is a polyester fiber having a birefringence of 0.025 or more, and the surface of the fiber is coated with a finishing agent of 0.4 to 1.2% by weight, containing compounds (1) to (4) as essential components of the finishing agent, and compounds (1) to (4) in the total amount of the finishing agent. (4) Polyester fiber characterized by having a total content of 80 to 100% by weight.

(1) An aliphatic ester having a molecular weight of 300 to 800 and a content of 50 to 70% by weight with respect to the total amount of the finishing agent, and / or a resin with a viscosity of 40 to 50 at 30 ° C. 0 second mineral oil

(2) A content of 5 to 30% by weight based on the total amount of the finishing agent, represented by the following structural formula, in which an ethylene oxide unit and a propylene oxide unit are randomly or block copolymerized. Polyether

R, — 0— (CH ₂ CH ₂ 0) n! -(CH (CH ₃ ) CH ₂ 0) n ₂ -R ₂

(Here,, R 2 are a hydrogen atom, an organic group having 1 to 50 carbon atoms, and n ₂ is 1 to 100.)

(3) Alcohols, carboxylic acids, amines, amines having 1 to 30 carbon atoms A compound in which ethylene oxide or propylene oxide is added to at least one member selected from the group consisting of: 5 to 30% by weight of nonionic surfactant

(4) An ionic surfactant having a content of 5 to 15% by weight based on the total amount of the finishing agent

8.9% by weight or more of polytrimethylene terephthalate is composed of polyester fibers having a birefringence of 0.025 or more, and the fiber-to-fiber dynamic friction coefficient is 0.3 to 0.4. 5. Polyester fibers having a fiber-to-metal kinetic friction coefficient of 0.17 to 0.3.

9.9% by weight or more of polytrimethylene terephthalate is a polyester fiber having a birefringence of not less than 0.025 and a fiber-to-fiber dynamic friction coefficient of 0.3 to 0.3. 45. A polyester fiber having a fiber-to-metal kinetic friction coefficient of 0.17 to 0.3 and a fiber-fiber static friction coefficient of 0.27 to 0.4.